Leukocytes Quiz

Overview of Leukocytes and their Types

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate for only a few hours in the peripheral blood before migrating to tissues.
• Leukocytes defend the body against foreign invaders and are attracted to sites of inflammation, infection, or tissue injury by chemoattractants.
• There are three main types of hematopoietic cells: stem cells, progenitor cells, and precursor cells.
• Myeloblasts differentiate into promyelocytes, myelocytes, metamyelocytes, and finally, neutrophils.
• The five types of human leukocytes are neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils constitute 40-60% of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils spend very little time in peripheral blood before migrating to tissues and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute less than 1% of total leukocytes, have a bilobed nucleus, and large purple-black granules containing histamine and heparin.
• Monocytes are the largest cells in peripheral blood and function as phagocytes, ingesting and killing microorganisms.
• Lymphocytes are classified as T and B lymphocytes and are responsible for cell-mediated and humoral immunity, respectively.

Overview of Leukocytes and their Types

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate for only a few hours in the peripheral blood before migrating to tissues.
• Leukocytes defend the body against foreign invaders and are attracted to sites of inflammation, infection, or tissue injury by chemoattractants.
• There are three main types of hematopoietic cells: stem cells, progenitor cells, and precursor cells.
• Myeloblasts differentiate into promyelocytes, myelocytes, metamyelocytes, and finally, neutrophils.
• The five types of human leukocytes are neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils constitute 40-60% of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils spend very little time in peripheral blood before migrating to tissues and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute less than 1% of total leukocytes, have a bilobed nucleus, and large purple-black granules containing histamine and heparin.
• Monocytes are the largest cells in peripheral blood and function as phagocytes, ingesting and killing microorganisms.
• Lymphocytes are classified as T and B lymphocytes and are responsible for cell-mediated and humoral immunity, respectively.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow under the influence of hematopoietic growth factors.
• Stem cells mature into terminally differentiated cells that circulate for a few hours in peripheral blood before migrating to tissues.
• Leukocytes serve as defenders of the body against foreign invaders and are attracted to sites of inflammation, infection, or tissue injury by chemoattractants.
• Hematopoietic cells differentiate into stem cells, lymphoid and myeloid multipotential cells, progenitor cells, colony-forming cells, precursor cells, and mature cells.
• Myelopoiesis involves the differentiation of myeloblasts into promyelocytes, myelocytes, metamyelocytes, and mature neutrophils with segmented nuclei.
• The five types of human leukocytes include neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils constitute the majority of circulatory leukocytes and have an average lifespan of 10 hours before moving to tissues through the blood vessel wall.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute less than 1% of leukocytes and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood, leave the blood and enter the tissues, where they mature into macrophages, and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocytes with two types, T and B lymphocytes, account for 20-40% of leukocytes and are responsible for cell-mediated and humoral immunity.
• WBC count, types, and function can be obtained from CBC, DLC, and PBF, and normal range for total leukocyte count is 4,000-11,000/mm3 in adults, with a lower count than RBCs due to a shorter lifespan.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow under the influence of hematopoietic growth factors.
• Stem cells mature into terminally differentiated cells that circulate for a few hours in peripheral blood before migrating to tissues.
• Leukocytes serve as defenders of the body against foreign invaders and are attracted to sites of inflammation, infection, or tissue injury by chemoattractants.
• Hematopoietic cells differentiate into stem cells, lymphoid and myeloid multipotential cells, progenitor cells, colony-forming cells, precursor cells, and mature cells.
• Myelopoiesis involves the differentiation of myeloblasts into promyelocytes, myelocytes, metamyelocytes, and mature neutrophils with segmented nuclei.
• The five types of human leukocytes include neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils constitute the majority of circulatory leukocytes and have an average lifespan of 10 hours before moving to tissues through the blood vessel wall.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute less than 1% of leukocytes and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood, leave the blood and enter the tissues, where they mature into macrophages, and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocytes with two types, T and B lymphocytes, account for 20-40% of leukocytes and are responsible for cell-mediated and humoral immunity.
• WBC count, types, and function can be obtained from CBC, DLC, and PBF, and normal range for total leukocyte count is 4,000-11,000/mm3 in adults, with a lower count than RBCs due to a shorter lifespan.

Introduction to Hematology: Characteristics and Functions of Blood

• Hematology is the study of blood and blood-forming tissues, including their formation, function, and associated diseases.
• Blood is composed of plasma and cellular elements, including leukocytes, platelets, and erythrocytes.
• Plasma makes up approximately 55% of the blood volume, while erythrocytes make up 45%, and leukocytes and platelets make up 1%.
• The principal component of plasma is water, which contains various dissolved ions, proteins, carbohydrates, fats, hormones, vitamins, and enzymes.
• The main protein constituent of plasma is albumin, which acts as a carrier molecule for compounds such as bilirubin and heme.
• Other blood proteins carry vitamins, minerals, and lipids, while immunoglobulins and complements are involved in immune defense.
• Erythrocytes contain hemoglobin, which is responsible for transporting oxygen and carbon dioxide between the lungs and body tissues.
• Leukocytes defend the body against foreign antigens, such as bacteria and viruses.
• Platelets are necessary for maintaining hemostasis.
• Blood comprises 8% of the body weight, with a volume of 4-5 L in females and 5-6 L in males.
• The temperature of blood is 37-38°C, with a pH of 7.35-7.45 and a viscosity of 4.5-5.5 relative to water.
• Blood is composed of plasma (90% water and 10% other substances) and formed elements (red blood cells, white blood cells, and platelets), with plasma containing various proteins such as albumin, globulins, and fibrinogen.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Haematopoiesis: The Process of Blood Cell Production

• Haematopoiesis is the production of different types of blood cells.
• This process depends on the proliferation of precursor cells that retain mitotic capability and is regulated by cytokines.
• The replacement of circulating mature blood cells depends on the function of hematopoietic precursor cells.
• There are three types of hematopoiesis: erythropoiesis, leukopoiesis, and thrombopoiesis.
• Haematopoiesis takes place in hematopoietic organs, primarily in bone marrow in adults.
• The process of haematopoiesis involves careful balance between cellular proliferation, differentiation, and cell death.
• Hematopoietic precursor cells are divided into three cellular compartments: stem cells, progenitor cells, and maturing cells.
• Stem cells are pluripotential and give rise to all lineages of blood cells.
• Progenitor cells have restricted development potential and include colony-forming units (CFUs) that produce different types of blood cells.
• Maturing cells constitute more than 95% of total hematopoietic cells and are morphologically recognizable.
• Hematopoietic precursor cell survival, self-renewal, proliferation, and differentiation are regulated by hematopoietic growth factors or cytokines.
• The hematopoietic microenvironment, which includes stromal cells and extracellular matrix, is crucial for the development of hematopoietic cells.

Haematopoiesis: The Process of Blood Cell Production

• Haematopoiesis is the production of different types of blood cells.
• This process depends on the proliferation of precursor cells that retain mitotic capability and is regulated by cytokines.
• The replacement of circulating mature blood cells depends on the function of hematopoietic precursor cells.
• There are three types of hematopoiesis: erythropoiesis, leukopoiesis, and thrombopoiesis.
• Haematopoiesis takes place in hematopoietic organs, primarily in bone marrow in adults.
• The process of haematopoiesis involves careful balance between cellular proliferation, differentiation, and cell death.
• Hematopoietic precursor cells are divided into three cellular compartments: stem cells, progenitor cells, and maturing cells.
• Stem cells are pluripotential and give rise to all lineages of blood cells.
• Progenitor cells have restricted development potential and include colony-forming units (CFUs) that produce different types of blood cells.
• Maturing cells constitute more than 95% of total hematopoietic cells and are morphologically recognizable.
• Hematopoietic precursor cell survival, self-renewal, proliferation, and differentiation are regulated by hematopoietic growth factors or cytokines.
• The hematopoietic microenvironment, which includes stromal cells and extracellular matrix, is crucial for the development of hematopoietic cells.

Introduction to Hematology: Characteristics and Functions of Blood

• Hematology is the study of blood and blood-forming tissues, including their formation, function, and associated diseases.
• Blood is composed of plasma and cellular elements, including leukocytes, platelets, and erythrocytes.
• Plasma makes up approximately 55% of the blood volume, while erythrocytes make up 45%, and leukocytes and platelets make up 1%.
• The principal component of plasma is water, which contains various dissolved ions, proteins, carbohydrates, fats, hormones, vitamins, and enzymes.
• The main protein constituent of plasma is albumin, which acts as a carrier molecule for compounds such as bilirubin and heme.
• Other blood proteins carry vitamins, minerals, and lipids, while immunoglobulins and complements are involved in immune defense.
• Erythrocytes contain hemoglobin, which is responsible for transporting oxygen and carbon dioxide between the lungs and body tissues.
• Leukocytes defend the body against foreign antigens, such as bacteria and viruses.
• Platelets are necessary for maintaining hemostasis.
• Blood comprises 8% of the body weight, with a volume of 4-5 L in females and 5-6 L in males.
• The temperature of blood is 37-38°C, with a pH of 7.35-7.45 and a viscosity of 4.5-5.5 relative to water.
• Blood is composed of plasma (90% water and 10% other substances) and formed elements (red blood cells, white blood cells, and platelets), with plasma containing various proteins such as albumin, globulins, and fibrinogen.

Introduction to Hematology: Characteristics and Functions of Blood

• Hematology is the study of blood and blood-forming tissues, including their formation, function, and associated diseases.
• Blood is composed of plasma and cellular elements, including leukocytes, platelets, and erythrocytes.
• Plasma makes up approximately 55% of the blood volume, while erythrocytes make up 45%, and leukocytes and platelets make up 1%.
• The principal component of plasma is water, which contains various dissolved ions, proteins, carbohydrates, fats, hormones, vitamins, and enzymes.
• The main protein constituent of plasma is albumin, which acts as a carrier molecule for compounds such as bilirubin and heme.
• Other blood proteins carry vitamins, minerals, and lipids, while immunoglobulins and complements are involved in immune defense.
• Erythrocytes contain hemoglobin, which is responsible for transporting oxygen and carbon dioxide between the lungs and body tissues.
• Leukocytes defend the body against foreign antigens, such as bacteria and viruses.
• Platelets are necessary for maintaining hemostasis.
• Blood comprises 8% of the body weight, with a volume of 4-5 L in females and 5-6 L in males.
• The temperature of blood is 37-38°C, with a pH of 7.35-7.45 and a viscosity of 4.5-5.5 relative to water.
• Blood is composed of plasma (90% water and 10% other substances) and formed elements (red blood cells, white blood cells, and platelets), with plasma containing various proteins such as albumin, globulins, and fibrinogen.

Introduction to Hematology: Characteristics and Functions of Blood

• Hematology is the study of blood and blood-forming tissues, including their formation, function, and associated diseases.
• Blood is composed of plasma and cellular elements, including leukocytes, platelets, and erythrocytes.
• Plasma comprises approximately 55% of the blood volume, while erythrocytes comprise 45%, and leukocytes and platelets comprise 1%.
• The principal component of plasma is water, which contains ions, proteins, carbohydrates, fats, hormones, vitamins, and enzymes necessary for normal cell function.
• The main protein constituent of plasma is albumin, which acts as a carrier molecule for compounds such as bilirubin and heme.
• Immunoglobulins and complements are specialized blood proteins involved in immune defense, while coagulation proteins maintain normal hemostasis.
• Erythrocytes contain hemoglobin, which is responsible for transporting oxygen and carbon dioxide between the lungs and body tissues.
• Leukocytes defend the body against foreign antigens such as bacteria and viruses.
• Platelets are necessary for maintaining hemostasis.
• Whole blood is bright dark red, comprises 8% of body weight, and has a volume of 4-5 L in females and 5-6 L in males, with a temperature of 37-38C and pH of 7.35-7.45.
• Plasma is the liquid part of blood, comprising 90% water and 10% other substances, including plasma proteins (albumin, globulins, fibrinogen) and inorganic substances (Na, K, HCO3, Ca).
• The functions of blood include transporting oxygen, nutrients, hormones, and waste products; maintaining normal acid-base balance, body temperature, and water balance; delivering specialized cells for tissue protection; and preventing leakage by closing holes in blood vessels.

Introduction to Hematology: Characteristics and Functions of Blood

• Hematology is the study of blood and blood-forming tissues, including their formation, function, and associated diseases.
• Blood is composed of plasma and cellular elements, including leukocytes, platelets, and erythrocytes.
• Plasma comprises approximately 55% of the blood volume, while erythrocytes comprise 45%, and leukocytes and platelets comprise 1%.
• The principal component of plasma is water, which contains ions, proteins, carbohydrates, fats, hormones, vitamins, and enzymes necessary for normal cell function.
• The main protein constituent of plasma is albumin, which acts as a carrier molecule for compounds such as bilirubin and heme.
• Immunoglobulins and complements are specialized blood proteins involved in immune defense, while coagulation proteins maintain normal hemostasis.
• Erythrocytes contain hemoglobin, which is responsible for transporting oxygen and carbon dioxide between the lungs and body tissues.
• Leukocytes defend the body against foreign antigens such as bacteria and viruses.
• Platelets are necessary for maintaining hemostasis.
• Whole blood is bright dark red, comprises 8% of body weight, and has a volume of 4-5 L in females and 5-6 L in males, with a temperature of 37-38C and pH of 7.35-7.45.
• Plasma is the liquid part of blood, comprising 90% water and 10% other substances, including plasma proteins (albumin, globulins, fibrinogen) and inorganic substances (Na, K, HCO3, Ca).
• The functions of blood include transporting oxygen, nutrients, hormones, and waste products; maintaining normal acid-base balance, body temperature, and water balance; delivering specialized cells for tissue protection; and preventing leakage by closing holes in blood vessels.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate in the peripheral blood for only a few hours before migrating to the tissues.
• Leukocytes serve as defenders of the body against foreign invaders.
• Hematopoietic cells differentiate into stem cells, progenitor cells, precursor cells, and mature cells.
• Myelopoiesis is the process of granulocytic cell differentiation.
• There are five types of human leukocytes: neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils are the majority of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute from 0-1% of the total leukocyte and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocyte and account between 20-40% function of lymphocyte.

Erythrocyte: Formation, Maturation, and Membrane

• Erythrocyte refers to the formation of red blood cells, which have a circulating lifespan of approximately 120 ± 10 days.
• Erythroid progenitor cells begin with hematopoietic stem cells (HSC) and differentiate into committed erythroid progenitor cells, consisting of burst-forming unit-erythroid(BFU-E) and colony-forming unit-erythroid(CFU-E).
• The process of erythroid maturing cells formation includes six morphologically defined stages: Basophilic Normoblast, Polychromatic Normoblast, Orthochromatic Normoblast, Reticulocyte, and Erythrocyte.
• Normoblasts spend from 5 to 7 days in the proliferating and maturing compartment of the bone marrow, and after reaching the reticulocyte stage, there is an additional 2-3 days of maturation before it is released to the peripheral blood.
• Reticulocytes are immature RBCs that do not contain a nucleus but contain residual ribosomal RNA and remain in the bone marrow for 1-2 days before being released into circulation.
• Erythrocytes are flat biconcave discs, non-nucleated, have a diameter of 7-8 µm, and a flexible structure. Females have 4.8 million erythrocytes, while males have 5.5 million erythrocytes.
• Erythropoietin (EPO) is the only cytokine important in regulating the final stages of erythroid maturation, and androgen appears to stimulate EPO secretion.
• Erythropoiesis is stimulated by Erythropoietin hormone produced by the kidney in response to hypoxia, which can be caused by low RBC count (anemia), hemorrhage, high altitude, exercise, prolonged heart failure, and lung disease.
• The erythrocyte membrane is a phospholipid bilayer-protein complex composed of 52% protein, 40% lipid, and 8% carbohydrate.
• The erythrocyte membrane has two types of proteins: integral and peripheral. Integral proteins include transport proteins and glycophorins, while peripheral proteins include spectrin and ankyrin, which serve as skeletal support for the membrane lipid bilayer.
• The deformability of the red cell is due to its biconcave shape, the viscosity of hemoglobin, and the viscoelastic properties of erythrocyte membrane.
• The function of the RBC membrane is to maintain erythrocyte's biconcave shape, provide deformability, elasticity, permeability, and contain blood group antigens.

Haematopoiesis: The Process of Blood Cell Production

• Haematopoiesis is the production of different types of blood cells.
• This process depends on the proliferation of precursor cells that retain mitotic capability and is regulated by cytokines.
• The replacement of circulating mature blood cells depends on the function of hematopoietic precursor cells.
• There are three types of hematopoiesis: erythropoiesis, leukopoiesis, and thrombopoiesis.
• Haematopoiesis takes place in hematopoietic organs, primarily in bone marrow in adults.
• The process of haematopoiesis involves careful balance between cellular proliferation, differentiation, and cell death.
• Hematopoietic precursor cells are divided into three cellular compartments: stem cells, progenitor cells, and maturing cells.
• Stem cells are pluripotential and give rise to all lineages of blood cells.
• Progenitor cells have restricted development potential and include colony-forming units (CFUs) that produce different types of blood cells.
• Maturing cells constitute more than 95% of total hematopoietic cells and are morphologically recognizable.
• Hematopoietic precursor cell survival, self-renewal, proliferation, and differentiation are regulated by hematopoietic growth factors or cytokines.
• The hematopoietic microenvironment, which includes stromal cells and extracellular matrix, is crucial for the development of hematopoietic cells.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate in the peripheral blood for only a few hours before migrating to the tissues.
• Leukocytes serve as defenders of the body against foreign invaders.
• Hematopoietic cells differentiate into stem cells, progenitor cells, precursor cells, and mature cells.
• Myelopoiesis is the process of granulocytic cell differentiation.
• There are five types of human leukocytes: neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils are the majority of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute from 0-1% of the total leukocyte and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocyte and account between 20-40% function of lymphocyte.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate in the peripheral blood for only a few hours before migrating to the tissues.
• Leukocytes serve as defenders of the body against foreign invaders.
• Hematopoietic cells differentiate into stem cells, progenitor cells, precursor cells, and mature cells.
• Myelopoiesis is the process of granulocytic cell differentiation.
• There are five types of human leukocytes: neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils are the majority of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute from 0-1% of the total leukocyte and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocyte and account between 20-40% function of lymphocyte.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate in the peripheral blood for only a few hours before migrating to the tissues.
• Leukocytes serve as defenders of the body against foreign invaders.
• Hematopoietic cells differentiate into stem cells, progenitor cells, precursor cells, and mature cells.
• Myelopoiesis is the process of granulocytic cell differentiation.
• There are five types of human leukocytes: neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils are the majority of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute from 0-1% of the total leukocyte and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocyte and account between 20-40% function of lymphocyte.

Overview of Leukocyte Development and Function

• Leukocytes develop from pluripotential stem cells in the bone marrow.
• Hematopoietic growth factors influence stem cells to mature into terminally differentiated cells.
• Leukocytes circulate in the peripheral blood for only a few hours before migrating to the tissues.
• Leukocytes serve as defenders of the body against foreign invaders.
• Hematopoietic cells differentiate into stem cells, progenitor cells, precursor cells, and mature cells.
• Myelopoiesis is the process of granulocytic cell differentiation.
• There are five types of human leukocytes: neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
• Neutrophils are the majority of circulatory leukocytes and have a segmented nucleus with two to four lobes.
• Eosinophils have a concentration in peripheral blood from 1-3% and are associated with allergic reactions, parasite infection, and chronic inflammation.
• Basophils constitute from 0-1% of the total leukocyte and function as mediators of inflammatory responses, especially those of hypersensitivity and allergic reactions.
• Monocytes are the largest cells in the peripheral blood and function as phagocytes.
• Lymphocytes generally classified as large and mature lymphocyte and account between 20-40% function of lymphocyte.

Overview of Enteroviruses and Poliovirus

• Enteroviruses belong to the Picornaviridae family and are RNA viruses of group IV Baltimore.
• The four categories of enteroviruses are polioviruses, Coxsackie A viruses, Coxsackie B viruses, and echoviruses.
• Coxsackie A, Coxsackie B, and echoviruses are non-polio enteroviruses that can cause mild to severe illnesses in people, especially those with weak immune systems.
• Enteroviruses spread through the fecal-oral route and can cause hand, foot, and mouth disease, myocarditis, meningitis, and pancreatitis.
• Poliovirus is a rare paralytic illness caused by a virus that infects nerve cells in the spinal cord, brain stem, or motor cortex.
• Poliovirus transmission occurs mainly through the feces of infected people, and symptoms include fever, headache, and sore throat.
• The immune response to poliovirus includes an initial IgM response followed by IgG, which helps prevent re-infection.
• There are two forms of poliovirus vaccine: live attenuated (OPV) and inactivated (IPV).
• OPV induces blood and mucosal immune response against all three serotypes of poliovirus and is safe and effective.
• IPV is administered through injection and induces a stronger protective immune response than OPV, but it is more expensive and requires qualified health workers and sterile equipment.
• The lab diagnosis of poliovirus can be done through electron microscope, cell culture, or PCR, and serology can be useful in determining if a patient has paralytic poliomyelitis.
• Vaccine-derived polioviruses and rare cases of vaccine-associated paralytic polio are potential disadvantages of poliovirus vaccination.

Overview of Enteroviruses and Poliovirus

• Enteroviruses belong to the Picornaviridae family and are RNA viruses of group IV Baltimore.
• The four categories of enteroviruses are polioviruses, Coxsackie A viruses, Coxsackie B viruses, and echoviruses.
• Coxsackie A, Coxsackie B, and echoviruses are non-polio enteroviruses that can cause mild to severe illnesses in people, especially those with weak immune systems.
• Enteroviruses spread through the fecal-oral route and can cause hand, foot, and mouth disease, myocarditis, meningitis, and pancreatitis.
• Poliovirus is a rare paralytic illness caused by a virus that infects nerve cells in the spinal cord, brain stem, or motor cortex.
• Poliovirus transmission occurs mainly through the feces of infected people, and symptoms include fever, headache, and sore throat.
• The immune response to poliovirus includes an initial IgM response followed by IgG, which helps prevent re-infection.
• There are two forms of poliovirus vaccine: live attenuated (OPV) and inactivated (IPV).
• OPV induces blood and mucosal immune response against all three serotypes of poliovirus and is safe and effective.
• IPV is administered through injection and induces a stronger protective immune response than OPV, but it is more expensive and requires qualified health workers and sterile equipment.
• The lab diagnosis of poliovirus can be done through electron microscope, cell culture, or PCR, and serology can be useful in determining if a patient has paralytic poliomyelitis.
• Vaccine-derived polioviruses and rare cases of vaccine-associated paralytic polio are potential disadvantages of poliovirus vaccination.

Overview of Enteroviruses and Poliovirus

• Enteroviruses belong to the Picornaviridae family and are RNA viruses of group IV Baltimore.
• The four categories of enteroviruses are polioviruses, Coxsackie A viruses, Coxsackie B viruses, and echoviruses.
• Coxsackie A, Coxsackie B, and echoviruses are non-polio enteroviruses that can cause mild to severe illnesses in people, especially those with weak immune systems.
• Enteroviruses spread through the fecal-oral route and can cause hand, foot, and mouth disease, myocarditis, meningitis, and pancreatitis.
• Poliovirus is a rare paralytic illness caused by a virus that infects nerve cells in the spinal cord, brain stem, or motor cortex.
• Poliovirus transmission occurs mainly through the feces of infected people, and symptoms include fever, headache, and sore throat.
• The immune response to poliovirus includes an initial IgM response followed by IgG, which helps prevent re-infection.
• There are two forms of poliovirus vaccine: live attenuated (OPV) and inactivated (IPV).
• OPV induces blood and mucosal immune response against all three serotypes of poliovirus and is safe and effective.
• IPV is administered through injection and induces a stronger protective immune response than OPV, but it is more expensive and requires qualified health workers and sterile equipment.
• The lab diagnosis of poliovirus can be done through electron microscope, cell culture, or PCR, and serology can be useful in determining if a patient has paralytic poliomyelitis.
• Vaccine-derived polioviruses and rare cases of vaccine-associated paralytic polio are potential disadvantages of poliovirus vaccination.

Overview of Enteroviruses and Poliovirus

• Enteroviruses belong to the Picornaviridae family and are RNA viruses of group IV Baltimore.
• The four categories of enteroviruses are polioviruses, Coxsackie A viruses, Coxsackie B viruses, and echoviruses.
• Coxsackie A, Coxsackie B, and echoviruses are non-polio enteroviruses that can cause mild to severe illnesses in people, especially those with weak immune systems.
• Enteroviruses spread through the fecal-oral route and can cause hand, foot, and mouth disease, myocarditis, meningitis, and pancreatitis.
• Poliovirus is a rare paralytic illness caused by a virus that infects nerve cells in the spinal cord, brain stem, or motor cortex.
• Poliovirus transmission occurs mainly through the feces of infected people, and symptoms include fever, headache, and sore throat.
• The immune response to poliovirus includes an initial IgM response followed by IgG, which helps prevent re-infection.
• There are two forms of poliovirus vaccine: live attenuated (OPV) and inactivated (IPV).
• OPV induces blood and mucosal immune response against all three serotypes of poliovirus and is safe and effective.
• IPV is administered through injection and induces a stronger protective immune response than OPV, but it is more expensive and requires qualified health workers and sterile equipment.
• The lab diagnosis of poliovirus can be done through electron microscope, cell culture, or PCR, and serology can be useful in determining if a patient has paralytic poliomyelitis.
• Vaccine-derived polioviruses and rare cases of vaccine-associated paralytic polio are potential disadvantages of poliovirus vaccination.

Overview of Enteroviruses and Poliovirus

• Enteroviruses belong to the Picornaviridae family and are RNA viruses of group IV Baltimore.
• The four categories of enteroviruses are polioviruses, Coxsackie A viruses, Coxsackie B viruses, and echoviruses.
• Coxsackie A, Coxsackie B, and echoviruses are non-polio enteroviruses that can cause mild to severe illnesses in people, especially those with weak immune systems.
• Enteroviruses spread through the fecal-oral route and can cause hand, foot, and mouth disease, myocarditis, meningitis, and pancreatitis.
• Poliovirus is a rare paralytic illness caused by a virus that infects nerve cells in the spinal cord, brain stem, or motor cortex.
• Poliovirus transmission occurs mainly through the feces of infected people, and symptoms include fever, headache, and sore throat.
• The immune response to poliovirus includes an initial IgM response followed by IgG, which helps prevent re-infection.
• There are two forms of poliovirus vaccine: live attenuated (OPV) and inactivated (IPV).
• OPV induces blood and mucosal immune response against all three serotypes of poliovirus and is safe and effective.
• IPV is administered through injection and induces a stronger protective immune response than OPV, but it is more expensive and requires qualified health workers and sterile equipment.
• The lab diagnosis of poliovirus can be done through electron microscope, cell culture, or PCR, and serology can be useful in determining if a patient has paralytic poliomyelitis.
• Vaccine-derived polioviruses and rare cases of vaccine-associated paralytic polio are potential disadvantages of poliovirus vaccination.

Introduction to Fungal Pathogens and Their Characteristics

• Mycology is the study of fungi, including molds, yeasts, and mushrooms.
• Fungi are eukaryotic organisms with complex carbohydrate cell walls and ergosterol as a major membrane sterol.
• Fungal structure includes hyphae that come together to form the mycelium, which can be classified as vegetative or aerial.
• Conidia are spore-like asexual reproductive structures that are important for fungal identification and classification.
• Fungi can reproduce sexually or asexually, with different types of spores produced in each case.
• Fungal cultures can be grown on different types of media, including general-purpose, selective, and differential agars.
• Direct examination methods include saline wet mounts, lactophenol cotton blue wet mounts, potassium hydroxide (KOH) mounts, gram stains, India ink, and calcofluor white stains.
• Fungal pathogens can infect various body sites, including blood, cerebrospinal fluid, hair, nails, skin, lungs, throat, urine, and genital tract.
• Candida spp., Aspergillus, Histoplasma capsulatum, and Cryptococcus neoformans are among the common fungal pathogens found in these body sites.
• Systemic mycosis is a multiorgan infection caused by fungi, while opportunistic mycosis occurs primarily in immunocompromised patients.
• Dimorphic fungi can show both a yeast and a mold phase, while saprobes can live on decaying organic material.
• Fungal infections can be treated with antifungal medications that target ergosterol synthesis or bind to ergosterol in the fungal membrane.

Introduction to Fungal Pathogens and Their Characteristics

• Mycology is the study of fungi, including molds, yeasts, and mushrooms.
• Fungi are eukaryotic organisms with complex carbohydrate cell walls and ergosterol as a major membrane sterol.
• Fungal structure includes hyphae that come together to form the mycelium, which can be classified as vegetative or aerial.
• Conidia are spore-like asexual reproductive structures that are important for fungal identification and classification.
• Fungi can reproduce sexually or asexually, with different types of spores produced in each case.
• Fungal cultures can be grown on different types of media, including general-purpose, selective, and differential agars.
• Direct examination methods include saline wet mounts, lactophenol cotton blue wet mounts, potassium hydroxide (KOH) mounts, gram stains, India ink, and calcofluor white stains.
• Fungal pathogens can infect various body sites, including blood, cerebrospinal fluid, hair, nails, skin, lungs, throat, urine, and genital tract.
• Candida spp., Aspergillus, Histoplasma capsulatum, and Cryptococcus neoformans are among the common fungal pathogens found in these body sites.
• Systemic mycosis is a multiorgan infection caused by fungi, while opportunistic mycosis occurs primarily in immunocompromised patients.
• Dimorphic fungi can show both a yeast and a mold phase, while saprobes can live on decaying organic material.
• Fungal infections can be treated with antifungal medications that target ergosterol synthesis or bind to ergosterol in the fungal membrane.

Introduction to Fungal Pathogens and Their Characteristics

• Mycology is the study of fungi, including molds, yeasts, and mushrooms.
• Fungi are eukaryotic organisms with complex carbohydrate cell walls and ergosterol as a major membrane sterol.
• Fungal structure includes hyphae that come together to form the mycelium, which can be classified as vegetative or aerial.
• Conidia are spore-like asexual reproductive structures that are important for fungal identification and classification.
• Fungi can reproduce sexually or asexually, with different types of spores produced in each case.
• Fungal cultures can be grown on different types of media, including general-purpose, selective, and differential agars.
• Direct examination methods include saline wet mounts, lactophenol cotton blue wet mounts, potassium hydroxide (KOH) mounts, gram stains, India ink, and calcofluor white stains.
• Fungal pathogens can infect various body sites, including blood, cerebrospinal fluid, hair, nails, skin, lungs, throat, urine, and genital tract.
• Candida spp., Aspergillus, Histoplasma capsulatum, and Cryptococcus neoformans are among the common fungal pathogens found in these body sites.
• Systemic mycosis is a multiorgan infection caused by fungi, while opportunistic mycosis occurs primarily in immunocompromised patients.
• Dimorphic fungi can show both a yeast and a mold phase, while saprobes can live on decaying organic material.
• Fungal infections can be treated with antifungal medications that target ergosterol synthesis or bind to ergosterol in the fungal membrane.